Indoor Cat losing fur in clumps with dandruff in rump area

[Chate]

We have a 16.5 year old Bermese-mixed cat, who is (within the last 10 days) losing her fur in clumps.  She is an indoor cat.  Our other cat, who's 16 was raised with her with no signs of the same condition affecting her.  We have not changed her cat food and have not found any flea droppings on her at all.  The only changes in the house, was a recent loss of our 13 yr old dog and an addition of a 7 mo puppy in December.  There were no affects to the new addition and they have gotten along well in that the cat hisses and the puppy leaves the area.  I have started brushing her out, but it seems to exaserbate the problem and I've started to notice bald spots on her now.  It does seem as though there are large flakes of dandruff in her rump area but there are no color changes to the skin.  She has always been a little cat, but now seems more boney than ever despite her appetite.  We have not noticed any worms in her fecal matter.  She gets very stressed in the car and at the vets, so we avoid that if at all possible.

Any ideas of ways to help her?  Is this normal in an older cat?

[Aleda M Cheng, D.V.M., C.V.A]

It is not normal in an older cat.  

Some ideas for the skin condition are that your new puppy could have brought in some ecto-parasites into the house and these have infested your cat, or your cat could have developed food allergies (which can occur at any age), or this could be psychogenic alopecia, in that she is pulling out the hair due to stress or depression (possibly from the loss of your 13 year old dog and the arrival of the new puppy).  

I don't like the idea that she has become boney either.  Only some parasites can be visualized with the naked eye.  Most can only be seen under the microscope.  Therefore, although she gets stressed in the car on the way to the vets I think it is a good idea if you take her there to get this sorted out.,

[Chate]

Thank you so much for the advice.  We have made an appointment at the clinic for early next week.  I will let you know what is said.